It is known that, to clamp the aforementioned boards in the position required, the current method is to use wooden or metal supports nailed to the boards themselves or a U-shaped piece, also wooden, is made whose two arms are attached or nailed to the corresponding board.
The system just described has some drawbacks.
An initial drawback comes from the fact that the aforementioned supports are unwieldy and they do not always manage to provide a constant pressure on the whole board and at times they cause the board to move in a damaging way which could lead to work being carried out which is not up to standard. Furthermore, the supports have a substantial side bulk which often limits their use.
A further drawback arises from the fact that the U-shaped piece obstructs and affects the builder's work in the area between the two boards, making it necessary in certain cases to move the U-shaped piece with the subsequent possibility of changing the original layout.
A further system in use to maintain the position of the boards and keep them constrained, is the use of a piece of iron rod, generally the type used for reinforcing reinforced concrete. The piece of iron rod is attached to the board, bent into the U-shape and then constrained to the other.
The system just described also has its drawbacks. An initial drawback was found to be the insufficient stability and the little holding power of the piece of iron rod since it is not always possible to make a part accurately and then fix it firmly to the boards.
A second drawback appears to be that if, for some reason, it is necessary to detach the piece of rod from the board, it is almost always impossible to reuse it, therefore a new piece must be prepared every time. All this leads to time wasting, a useless consumption of the materials and consequent increases in the working costs.
A further system envisages the use of small metal clamps but even these have shown to have their drawbacks.
A drawback, which is extremely limiting, is due to the difficulty involved in positioning the small clamps on the board since these can slip. To prevent them slipping, it should be a simple matter of clamping them but this destroys the homogeneity of the hold and results in different pressure at the various points of the board, with the risk of triggering off clamping and stability problems.
A further drawback comes from the fact that the small clamps are subject to considerable wear and tear caused by the presence of sand, dust and other substances.